X-Git-Url: https://git.xonotic.org/?p=xonotic%2Fgmqcc.git;a=blobdiff_plain;f=ftepp.c;h=1d734305406602d4c48e0312554f2b5384e2f70f;hp=7b31a601f0a2d6f44ae9ff01c1c41273a23eb245;hb=2652353f507345d485aef3b4e5fba5b2267d9a60;hpb=cc1c197fc6c80721ae7c12e316cd06bcbc1a57a6

diff --git a/ftepp.c b/ftepp.c
index 7b31a60..1d73430 100644
--- a/ftepp.c
+++ b/ftepp.c
@@ -24,35 +24,47 @@
 #include "lexer.h"
 
 typedef struct {
-	bool on;
-	bool was_on;
-	bool had_else;
+    bool on;
+    bool was_on;
+    bool had_else;
 } ppcondition;
 
 typedef struct {
-	int   token;
-	char *value;
+    int   token;
+    char *value;
+    /* a copy from the lexer */
+    union {
+        vector v;
+        int    i;
+        double f;
+        int    t; /* type */
+    } constval;
 } pptoken;
 
 typedef struct {
-	lex_ctx ctx;
+    lex_ctx ctx;
 
-	char   *name;
-	char  **params;
-	/* yes we need an extra flag since `#define FOO x` is not the same as `#define FOO() x` */
-	bool    has_params;
+    char   *name;
+    char  **params;
+    /* yes we need an extra flag since `#define FOO x` is not the same as `#define FOO() x` */
+    bool    has_params;
 
-	pptoken *output;
+    pptoken **output;
 } ppmacro;
 
 typedef struct {
-	lex_file    *lex;
-	int          token;
-	bool         newline;
-	unsigned int errors;
+    lex_file    *lex;
+    int          token;
+    bool         newline;
+    unsigned int errors;
 
-	ppcondition *conditions;
-	ppmacro    **macros;
+    bool         output_on;
+    ppcondition *conditions;
+    ppmacro    **macros;
+
+    char        *output_string;
+
+    char        *itemname;
 } ftepp_t;
 
 #define ftepp_tokval(f) ((f)->lex->tok.value)
@@ -60,325 +72,1209 @@ typedef struct {
 
 static void ftepp_errorat(ftepp_t *ftepp, lex_ctx ctx, const char *fmt, ...)
 {
-	va_list ap;
+    va_list ap;
 
-	ftepp->errors++;
+    ftepp->errors++;
 
-	va_start(ap, fmt);
+    va_start(ap, fmt);
     con_vprintmsg(LVL_ERROR, ctx.file, ctx.line, "error", fmt, ap);
-	va_end(ap);
+    va_end(ap);
 }
 
 static void ftepp_error(ftepp_t *ftepp, const char *fmt, ...)
 {
-	va_list ap;
+    va_list ap;
 
-	ftepp->errors++;
+    ftepp->errors++;
 
-	va_start(ap, fmt);
+    va_start(ap, fmt);
     con_vprintmsg(LVL_ERROR, ftepp->lex->tok.ctx.file, ftepp->lex->tok.ctx.line, "error", fmt, ap);
-	va_end(ap);
+    va_end(ap);
 }
 
-ppmacro *ppmacro_new(lex_ctx ctx, const char *name)
+static bool GMQCC_WARN ftepp_warn(ftepp_t *ftepp, int warntype, const char *fmt, ...)
 {
-	ppmacro *macro = (ppmacro*)mem_a(sizeof(ppmacro));
-	memset(macro, 0, sizeof(*macro));
-	macro->name = util_strdup(name);
-	return macro;
+    va_list ap;
+    int lvl = LVL_WARNING;
+
+    if (!OPTS_WARN(warntype))
+        return false;
+
+    if (opts_werror) {
+	    lvl = LVL_ERROR;
+        ftepp->errors++;
+    }
+
+    va_start(ap, fmt);
+    con_vprintmsg(lvl, ftepp->lex->tok.ctx.file, ftepp->lex->tok.ctx.line, "error", fmt, ap);
+    va_end(ap);
+    return opts_werror;
 }
 
-void ppmacro_delete(ppmacro *self)
+static pptoken *pptoken_make(ftepp_t *ftepp)
 {
-	vec_free(self->params);
-	vec_free(self->output);
-	mem_d(self->name);
-	mem_d(self);
+    pptoken *token = (pptoken*)mem_a(sizeof(pptoken));
+    token->token = ftepp->token;
+#if 0
+    if (token->token == TOKEN_WHITE)
+        token->value = util_strdup(" ");
+    else
+#else
+        token->value = util_strdup(ftepp_tokval(ftepp));
+#endif
+    memcpy(&token->constval, &ftepp->lex->tok.constval, sizeof(token->constval));
+    return token;
 }
 
-ftepp_t* ftepp_init()
+static void pptoken_delete(pptoken *self)
 {
-	ftepp_t *ftepp;
+    mem_d(self->value);
+    mem_d(self);
+}
 
-	ftepp = (ftepp_t*)mem_a(sizeof(*ftepp));
-	memset(ftepp, 0, sizeof(*ftepp));
+static ppmacro *ppmacro_new(lex_ctx ctx, const char *name)
+{
+    ppmacro *macro = (ppmacro*)mem_a(sizeof(ppmacro));
+    memset(macro, 0, sizeof(*macro));
+    macro->name = util_strdup(name);
+    return macro;
+}
 
-	return ftepp;
+static void ppmacro_delete(ppmacro *self)
+{
+    size_t i;
+    for (i = 0; i < vec_size(self->params); ++i)
+        mem_d(self->params[i]);
+    vec_free(self->params);
+    for (i = 0; i < vec_size(self->output); ++i)
+        pptoken_delete(self->output[i]);
+    vec_free(self->output);
+    mem_d(self->name);
+    mem_d(self);
 }
 
-void ftepp_delete(ftepp_t *self)
+static ftepp_t* ftepp_new()
 {
-	vec_free(self->macros);
-	vec_free(self->conditions);
-	mem_d(self);
+    ftepp_t *ftepp;
+
+    ftepp = (ftepp_t*)mem_a(sizeof(*ftepp));
+    memset(ftepp, 0, sizeof(*ftepp));
+
+    ftepp->output_on = true;
+
+    return ftepp;
 }
 
-ppmacro* ftepp_macro_find(ftepp_t *ftepp, const char *name)
+static void ftepp_delete(ftepp_t *self)
 {
-	size_t i;
-	for (i = 0; i < vec_size(ftepp->macros); ++i) {
-		if (!strcmp(name, ftepp->macros[i]->name))
-			return ftepp->macros[i];
-	}
-	return NULL;
+    size_t i;
+    if (self->itemname)
+        mem_d(self->itemname);
+    for (i = 0; i < vec_size(self->macros); ++i)
+        ppmacro_delete(self->macros[i]);
+    vec_free(self->macros);
+    vec_free(self->conditions);
+    if (self->lex)
+        lex_close(self->lex);
+    mem_d(self);
+}
+
+static void ftepp_out(ftepp_t *ftepp, const char *str, bool ignore_cond)
+{
+    if (ignore_cond || ftepp->output_on)
+    {
+        size_t len;
+        char  *data;
+        len = strlen(str);
+        data = vec_add(ftepp->output_string, len);
+        memcpy(data, str, len);
+    }
+}
+
+static void ftepp_update_output_condition(ftepp_t *ftepp)
+{
+    size_t i;
+    ftepp->output_on = true;
+    for (i = 0; i < vec_size(ftepp->conditions); ++i)
+        ftepp->output_on = ftepp->output_on && ftepp->conditions[i].on;
+}
+
+static ppmacro* ftepp_macro_find(ftepp_t *ftepp, const char *name)
+{
+    size_t i;
+    for (i = 0; i < vec_size(ftepp->macros); ++i) {
+        if (!strcmp(name, ftepp->macros[i]->name))
+            return ftepp->macros[i];
+    }
+    return NULL;
+}
+
+static void ftepp_macro_delete(ftepp_t *ftepp, const char *name)
+{
+    size_t i;
+    for (i = 0; i < vec_size(ftepp->macros); ++i) {
+        if (!strcmp(name, ftepp->macros[i]->name)) {
+            vec_remove(ftepp->macros, i, 1);
+            return;
+        }
+    }
 }
 
 static inline int ftepp_next(ftepp_t *ftepp)
 {
-	return (ftepp->token = lex_do(ftepp->lex));
+    return (ftepp->token = lex_do(ftepp->lex));
 }
 
 /* Important: this does not skip newlines! */
 static bool ftepp_skipspace(ftepp_t *ftepp)
 {
-	if (ftepp->token != TOKEN_WHITE)
-		return true;
-	while (ftepp_next(ftepp) == TOKEN_WHITE) {}
-	return (ftepp->token < TOKEN_EOF);
+    if (ftepp->token != TOKEN_WHITE)
+        return true;
+    while (ftepp_next(ftepp) == TOKEN_WHITE) {}
+    if (ftepp->token >= TOKEN_EOF) {
+        ftepp_error(ftepp, "unexpected end of preprocessor directive");
+        return false;
+    }
+    return true;
 }
 
-/* if/ifdef/define handlers */
+/* this one skips EOLs as well */
+static bool ftepp_skipallwhite(ftepp_t *ftepp)
+{
+    if (ftepp->token != TOKEN_WHITE && ftepp->token != TOKEN_EOL)
+        return true;
+    do {
+        ftepp_next(ftepp);
+    } while (ftepp->token == TOKEN_WHITE || ftepp->token == TOKEN_EOL);
+    if (ftepp->token >= TOKEN_EOF) {
+        ftepp_error(ftepp, "unexpected end of preprocessor directive");
+        return false;
+    }
+    return true;
+}
+
+/**
+ * The huge macro parsing code...
+ */
+static bool ftepp_define_params(ftepp_t *ftepp, ppmacro *macro)
+{
+    do {
+        ftepp_next(ftepp);
+        if (!ftepp_skipspace(ftepp))
+            return false;
+        if (ftepp->token == ')')
+            break;
+        switch (ftepp->token) {
+            case TOKEN_IDENT:
+            case TOKEN_TYPENAME:
+            case TOKEN_KEYWORD:
+                break;
+            default:
+                ftepp_error(ftepp, "unexpected token in parameter list");
+                return false;
+        }
+        vec_push(macro->params, util_strdup(ftepp_tokval(ftepp)));
+        ftepp_next(ftepp);
+        if (!ftepp_skipspace(ftepp))
+            return false;
+    } while (ftepp->token == ',');
+    if (ftepp->token != ')') {
+        ftepp_error(ftepp, "expected closing paren after macro parameter list");
+        return false;
+    }
+    ftepp_next(ftepp);
+    /* skipspace happens in ftepp_define */
+    return true;
+}
+
+static bool ftepp_define_body(ftepp_t *ftepp, ppmacro *macro)
+{
+    pptoken *ptok;
+    while (ftepp->token != TOKEN_EOL && ftepp->token < TOKEN_EOF) {
+        ptok = pptoken_make(ftepp);
+        vec_push(macro->output, ptok);
+        ftepp_next(ftepp);
+    }
+    /* recursive expansion can cause EOFs here */
+    if (ftepp->token != TOKEN_EOL && ftepp->token != TOKEN_EOF) {
+        ftepp_error(ftepp, "unexpected junk after macro or unexpected end of file");
+        return false;
+    }
+    return true;
+}
+
+static bool ftepp_define(ftepp_t *ftepp)
+{
+    ppmacro *macro;
+    (void)ftepp_next(ftepp);
+    if (!ftepp_skipspace(ftepp))
+        return false;
+
+    switch (ftepp->token) {
+        case TOKEN_IDENT:
+        case TOKEN_TYPENAME:
+        case TOKEN_KEYWORD:
+            macro = ftepp_macro_find(ftepp, ftepp_tokval(ftepp));
+            if (macro && ftepp->output_on) {
+                if (ftepp_warn(ftepp, WARN_PREPROCESSOR, "redefining `%s`", ftepp_tokval(ftepp)))
+                    return false;
+                ftepp_macro_delete(ftepp, ftepp_tokval(ftepp));
+            }
+            macro = ppmacro_new(ftepp_ctx(ftepp), ftepp_tokval(ftepp));
+            break;
+        default:
+            ftepp_error(ftepp, "expected macro name");
+            return false;
+    }
+
+    (void)ftepp_next(ftepp);
+
+    if (ftepp->token == '(') {
+        macro->has_params = true;
+        if (!ftepp_define_params(ftepp, macro))
+            return false;
+    }
+
+    if (!ftepp_skipspace(ftepp))
+        return false;
+
+    if (!ftepp_define_body(ftepp, macro))
+        return false;
+
+    if (ftepp->output_on)
+        vec_push(ftepp->macros, macro);
+    else {
+        ppmacro_delete(macro);
+    }
+    return true;
+}
+
+/**
+ * When a macro is used we have to handle parameters as well
+ * as special-concatenation via ## or stringification via #
+ *
+ * Note: parenthesis can nest, so FOO((a),b) is valid, but only
+ * this kind of parens. Curly braces or [] don't count towards the
+ * paren-level.
+ */
+typedef struct {
+    pptoken **tokens;
+} macroparam;
+
+static void macroparam_clean(macroparam *self)
+{
+    size_t i;
+    for (i = 0; i < vec_size(self->tokens); ++i)
+        pptoken_delete(self->tokens[i]);
+    vec_free(self->tokens);
+}
+
+/* need to leave the last token up */
+static bool ftepp_macro_call_params(ftepp_t *ftepp, macroparam **out_params)
+{
+    macroparam *params = NULL;
+    pptoken    *ptok;
+    macroparam  mp;
+    size_t      parens = 0;
+    size_t      i;
+
+    if (!ftepp_skipallwhite(ftepp))
+        return false;
+    while (ftepp->token != ')') {
+        mp.tokens = NULL;
+        if (!ftepp_skipallwhite(ftepp))
+            return false;
+        while (parens || ftepp->token != ',') {
+            if (ftepp->token == '(')
+                ++parens;
+            else if (ftepp->token == ')') {
+                if (!parens)
+                    break;
+                --parens;
+            }
+            ptok = pptoken_make(ftepp);
+            vec_push(mp.tokens, ptok);
+            if (ftepp_next(ftepp) >= TOKEN_EOF) {
+                ftepp_error(ftepp, "unexpected EOF in macro call");
+                goto on_error;
+            }
+        }
+        vec_push(params, mp);
+        mp.tokens = NULL;
+        if (ftepp->token == ')')
+            break;
+        if (ftepp->token != ',') {
+            ftepp_error(ftepp, "expected closing paren or comma in macro call");
+            goto on_error;
+        }
+        if (ftepp_next(ftepp) >= TOKEN_EOF) {
+            ftepp_error(ftepp, "unexpected EOF in macro call");
+            goto on_error;
+        }
+    }
+    /* need to leave that up
+    if (ftepp_next(ftepp) >= TOKEN_EOF) {
+        ftepp_error(ftepp, "unexpected EOF in macro call");
+        goto on_error;
+    }
+    */
+    *out_params = params;
+    return true;
+
+on_error:
+    if (mp.tokens)
+        macroparam_clean(&mp);
+    for (i = 0; i < vec_size(params); ++i)
+        macroparam_clean(&params[i]);
+    vec_free(params);
+    return false;
+}
+
+static bool macro_params_find(ppmacro *macro, const char *name, size_t *idx)
+{
+    size_t i;
+    for (i = 0; i < vec_size(macro->params); ++i) {
+        if (!strcmp(macro->params[i], name)) {
+            *idx = i;
+            return true;
+        }
+    }
+    return false;
+}
+
+static void ftepp_stringify_token(ftepp_t *ftepp, pptoken *token)
+{
+    char        chs[2];
+    const char *ch;
+    chs[1] = 0;
+    switch (token->token) {
+        case TOKEN_STRINGCONST:
+            ch = token->value;
+            while (*ch) {
+                /* in preprocessor mode strings already are string,
+                 * so we don't get actual newline bytes here.
+                 * Still need to escape backslashes and quotes.
+                 */
+                switch (*ch) {
+                    case '\\': ftepp_out(ftepp, "\\\\", false); break;
+                    case '"':  ftepp_out(ftepp, "\\\"", false); break;
+                    default:
+                        chs[0] = *ch;
+                        ftepp_out(ftepp, chs, false);
+                        break;
+                }
+                ++ch;
+            }
+            break;
+        case TOKEN_WHITE:
+            ftepp_out(ftepp, " ", false);
+            break;
+        case TOKEN_EOL:
+            ftepp_out(ftepp, "\\n", false);
+            break;
+        default:
+            ftepp_out(ftepp, token->value, false);
+            break;
+    }
+}
+
+static void ftepp_stringify(ftepp_t *ftepp, macroparam *param)
+{
+    size_t i;
+    ftepp_out(ftepp, "\"", false);
+    for (i = 0; i < vec_size(param->tokens); ++i)
+        ftepp_stringify_token(ftepp, param->tokens[i]);
+    ftepp_out(ftepp, "\"", false);
+}
+
+static void ftepp_recursion_header(ftepp_t *ftepp)
+{
+    ftepp_out(ftepp, "\n#pragma push(line)\n", false);
+}
+
+static void ftepp_recursion_footer(ftepp_t *ftepp)
+{
+    ftepp_out(ftepp, "\n#pragma pop(line)\n", false);
+}
+
+static bool ftepp_preprocess(ftepp_t *ftepp);
+static bool ftepp_macro_expand(ftepp_t *ftepp, ppmacro *macro, macroparam *params)
+{
+    char     *old_string = ftepp->output_string;
+    lex_file *old_lexer = ftepp->lex;
+    bool retval = true;
+
+    size_t    o, pi, pv;
+    lex_file *inlex;
+
+    int nextok;
+
+    /* really ... */
+    if (!vec_size(macro->output))
+        return true;
+
+    ftepp->output_string = NULL;
+    for (o = 0; o < vec_size(macro->output); ++o) {
+        pptoken *out = macro->output[o];
+        switch (out->token) {
+            case TOKEN_IDENT:
+            case TOKEN_TYPENAME:
+            case TOKEN_KEYWORD:
+                if (!macro_params_find(macro, out->value, &pi)) {
+                    ftepp_out(ftepp, out->value, false);
+                    break;
+                } else {
+                    for (pv = 0; pv < vec_size(params[pi].tokens); ++pv) {
+                        out = params[pi].tokens[pv];
+                        if (out->token == TOKEN_EOL)
+                            ftepp_out(ftepp, "\n", false);
+                        else
+                            ftepp_out(ftepp, out->value, false);
+                    }
+                }
+                break;
+            case '#':
+                if (o + 1 < vec_size(macro->output)) {
+                    nextok = macro->output[o+1]->token;
+                    if (nextok == '#') {
+                        /* raw concatenation */
+                        ++o;
+                        break;
+                    }
+                    if ( (nextok == TOKEN_IDENT    ||
+                          nextok == TOKEN_KEYWORD  ||
+                          nextok == TOKEN_TYPENAME) &&
+                        macro_params_find(macro, macro->output[o+1]->value, &pi))
+                    {
+                        ++o;
+                        ftepp_stringify(ftepp, &params[pi]);
+                        break;
+                    }
+                }
+                ftepp_out(ftepp, "#", false);
+                break;
+            case TOKEN_EOL:
+                ftepp_out(ftepp, "\n", false);
+                break;
+            default:
+                ftepp_out(ftepp, out->value, false);
+                break;
+        }
+    }
+    vec_push(ftepp->output_string, 0);
+    /* Now run the preprocessor recursively on this string buffer */
+    /*
+    printf("__________\n%s\n=========\n", ftepp->output_string);
+    */
+    inlex = lex_open_string(ftepp->output_string, vec_size(ftepp->output_string)-1, ftepp->lex->name);
+    if (!inlex) {
+        ftepp_error(ftepp, "internal error: failed to instantiate lexer");
+        retval = false;
+        goto cleanup;
+    }
+    ftepp->output_string = old_string;
+    ftepp->lex = inlex;
+    ftepp_recursion_header(ftepp);
+    if (!ftepp_preprocess(ftepp)) {
+        lex_close(ftepp->lex);
+        retval = false;
+        goto cleanup;
+    }
+    ftepp_recursion_footer(ftepp);
+    old_string = ftepp->output_string;
+
+cleanup:
+    ftepp->lex           = old_lexer;
+    ftepp->output_string = old_string;
+    return retval;
+}
+
+static bool ftepp_macro_call(ftepp_t *ftepp, ppmacro *macro)
+{
+    size_t     o;
+    macroparam *params = NULL;
+    bool        retval = true;
+
+    if (!macro->has_params) {
+        if (!ftepp_macro_expand(ftepp, macro, NULL))
+            return false;
+        ftepp_next(ftepp);
+        return true;
+    }
+    ftepp_next(ftepp);
+
+    if (!ftepp_skipallwhite(ftepp))
+        return false;
+
+    if (ftepp->token != '(') {
+        ftepp_error(ftepp, "expected macro parameters in parenthesis");
+        return false;
+    }
+
+    ftepp_next(ftepp);
+    if (!ftepp_macro_call_params(ftepp, &params))
+        return false;
+
+    if (vec_size(params) != vec_size(macro->params)) {
+        ftepp_error(ftepp, "macro %s expects %u paramteters, %u provided", macro->name,
+                    (unsigned int)vec_size(macro->params),
+                    (unsigned int)vec_size(params));
+        retval = false;
+        goto cleanup;
+    }
+
+    if (!ftepp_macro_expand(ftepp, macro, params))
+        retval = false;
+    ftepp_next(ftepp);
+
+cleanup:
+    for (o = 0; o < vec_size(params); ++o)
+        macroparam_clean(&params[o]);
+    vec_free(params);
+    return retval;
+}
+
+/**
+ * #if - the FTEQCC way:
+ *    defined(FOO) => true if FOO was #defined regardless of parameters or contents
+ *    <numbers>    => True if the number is not 0
+ *    !<factor>    => True if the factor yields false
+ *    !!<factor>   => ERROR on 2 or more unary nots
+ *    <macro>      => becomes the macro's FIRST token regardless of parameters
+ *    <e> && <e>   => True if both expressions are true
+ *    <e> || <e>   => True if either expression is true
+ *    <string>     => False
+ *    <ident>      => False (remember for macros the <macro> rule applies instead)
+ * Unary + and - are weird and wrong in fteqcc so we don't allow them
+ * parenthesis in expressions are allowed
+ * parameter lists on macros are errors
+ * No mathematical calculations are executed
+ */
+static bool ftepp_if_expr(ftepp_t *ftepp, bool *out)
+{
+    ppmacro *macro;
+    bool     wasnot = false;
+
+    if (!ftepp_skipspace(ftepp))
+        return false;
+
+    while (ftepp->token == '!') {
+        wasnot = true;
+        ftepp_next(ftepp);
+        if (!ftepp_skipspace(ftepp))
+            return false;
+    }
+
+    switch (ftepp->token) {
+        case TOKEN_IDENT:
+        case TOKEN_TYPENAME:
+        case TOKEN_KEYWORD:
+            if (!strcmp(ftepp_tokval(ftepp), "defined")) {
+                ftepp_next(ftepp);
+                if (!ftepp_skipspace(ftepp))
+                    return false;
+                if (ftepp->token != '(') {
+                    ftepp_error(ftepp, "`defined` keyword in #if requires a macro name in parenthesis");
+                    return false;
+                }
+                ftepp_next(ftepp);
+                if (!ftepp_skipspace(ftepp))
+                    return false;
+                if (ftepp->token != TOKEN_IDENT &&
+                    ftepp->token != TOKEN_TYPENAME &&
+                    ftepp->token != TOKEN_KEYWORD)
+                {
+                    ftepp_error(ftepp, "defined() used on an unexpected token type");
+                    return false;
+                }
+                macro = ftepp_macro_find(ftepp, ftepp_tokval(ftepp));
+                *out = !!macro;
+                ftepp_next(ftepp);
+                if (!ftepp_skipspace(ftepp))
+                    return false;
+                if (ftepp->token != ')') {
+                    ftepp_error(ftepp, "expected closing paren");
+                    return false;
+                }
+                break;
+            }
+
+            macro = ftepp_macro_find(ftepp, ftepp_tokval(ftepp));
+            if (!macro || !vec_size(macro->output)) {
+                *out = false;
+            } else {
+                /* This does not expand recursively! */
+                switch (macro->output[0]->token) {
+                    case TOKEN_INTCONST:
+                        *out = !!(macro->output[0]->constval.f);
+                        break;
+                    case TOKEN_FLOATCONST:
+                        *out = !!(macro->output[0]->constval.f);
+                        break;
+                    default:
+                        *out = false;
+                        break;
+                }
+            }
+            break;
+        case TOKEN_STRINGCONST:
+            *out = false;
+            break;
+        case TOKEN_INTCONST:
+            *out = !!(ftepp->lex->tok.constval.i);
+            break;
+        case TOKEN_FLOATCONST:
+            *out = !!(ftepp->lex->tok.constval.f);
+            break;
+
+        case '(':
+            ftepp_next(ftepp);
+            if (!ftepp_if_expr(ftepp, out))
+                return false;
+            if (ftepp->token != ')') {
+                ftepp_error(ftepp, "expected closing paren in #if expression");
+                return false;
+            }
+            break;
+
+        default:
+            ftepp_error(ftepp, "junk in #if");
+            return false;
+    }
+    if (wasnot)
+        *out = !*out;
+
+    ftepp->lex->flags.noops = false;
+    ftepp_next(ftepp);
+    if (!ftepp_skipspace(ftepp))
+        return false;
+    ftepp->lex->flags.noops = true;
+
+    if (ftepp->token == ')')
+        return true;
+
+    if (ftepp->token != TOKEN_OPERATOR)
+        return true;
+
+    if (!strcmp(ftepp_tokval(ftepp), "&&") ||
+        !strcmp(ftepp_tokval(ftepp), "||"))
+    {
+        bool next = false;
+        char opc  = ftepp_tokval(ftepp)[0];
+
+        ftepp_next(ftepp);
+        if (!ftepp_if_expr(ftepp, &next))
+            return false;
+
+        if (opc == '&')
+            *out = *out && next;
+        else
+            *out = *out || next;
+        return true;
+    }
+    else {
+        ftepp_error(ftepp, "junk after #if");
+        return false;
+    }
+}
 
 static bool ftepp_if(ftepp_t *ftepp, ppcondition *cond)
 {
-	ftepp_error(ftepp, "TODO: #if");
-	return false;
+    bool result = false;
+
+    memset(cond, 0, sizeof(*cond));
+    (void)ftepp_next(ftepp);
+
+    if (!ftepp_skipspace(ftepp))
+        return false;
+    if (ftepp->token == TOKEN_EOL) {
+        ftepp_error(ftepp, "expected expression for #if-directive");
+        return false;
+    }
+
+    if (!ftepp_if_expr(ftepp, &result))
+        return false;
+
+    cond->on = result;
+    return true;
 }
 
+/**
+ * ifdef is rather simple
+ */
 static bool ftepp_ifdef(ftepp_t *ftepp, ppcondition *cond)
 {
-	ppmacro *macro;
-	(void)ftepp_next(ftepp);
-	if (!ftepp_skipspace(ftepp))
-		return false;
-
-	switch (ftepp->token) {
-		case TOKEN_IDENT:
-		case TOKEN_KEYWORD:
-			macro = ftepp_macro_find(ftepp, ftepp_tokval(ftepp));
-			break;
-		default:
-			ftepp_error(ftepp, "expected macro name");
-			return false;
-	}
-
-	(void)ftepp_next(ftepp);
-	if (!ftepp_skipspace(ftepp))
-		return false;
-	if (ftepp->token != TOKEN_EOL) {
-		ftepp_error(ftepp, "stray tokens after #ifdef");
-		return false;
-	}
-	cond->on = !!macro;
-	return true;
+    ppmacro *macro;
+    memset(cond, 0, sizeof(*cond));
+    (void)ftepp_next(ftepp);
+    if (!ftepp_skipspace(ftepp))
+        return false;
+
+    switch (ftepp->token) {
+        case TOKEN_IDENT:
+        case TOKEN_TYPENAME:
+        case TOKEN_KEYWORD:
+            macro = ftepp_macro_find(ftepp, ftepp_tokval(ftepp));
+            break;
+        default:
+            ftepp_error(ftepp, "expected macro name");
+            return false;
+    }
+
+    (void)ftepp_next(ftepp);
+    if (!ftepp_skipspace(ftepp))
+        return false;
+    /* relaxing this condition
+    if (ftepp->token != TOKEN_EOL && ftepp->token != TOKEN_EOF) {
+        ftepp_error(ftepp, "stray tokens after #ifdef");
+        return false;
+    }
+    */
+    cond->on = !!macro;
+    return true;
 }
 
-static bool ftepp_define(ftepp_t *ftepp)
+/**
+ * undef is also simple
+ */
+static bool ftepp_undef(ftepp_t *ftepp)
+{
+    (void)ftepp_next(ftepp);
+    if (!ftepp_skipspace(ftepp))
+        return false;
+
+    if (ftepp->output_on) {
+        switch (ftepp->token) {
+            case TOKEN_IDENT:
+            case TOKEN_TYPENAME:
+            case TOKEN_KEYWORD:
+                ftepp_macro_delete(ftepp, ftepp_tokval(ftepp));
+                break;
+            default:
+                ftepp_error(ftepp, "expected macro name");
+                return false;
+        }
+    }
+
+    (void)ftepp_next(ftepp);
+    if (!ftepp_skipspace(ftepp))
+        return false;
+    /* relaxing this condition
+    if (ftepp->token != TOKEN_EOL && ftepp->token != TOKEN_EOF) {
+        ftepp_error(ftepp, "stray tokens after #ifdef");
+        return false;
+    }
+    */
+    return true;
+}
+
+/* Special unescape-string function which skips a leading quote
+ * and stops at a quote, not just at \0
+ */
+static void unescape(const char *str, char *out) {
+    ++str;
+    while (*str && *str != '"') {
+        if (*str == '\\') {
+            ++str;
+            switch (*str) {
+                case '\\': *out++ = *str; break;
+                case '"':  *out++ = *str; break;
+                case 'a':  *out++ = '\a'; break;
+                case 'b':  *out++ = '\b'; break;
+                case 'r':  *out++ = '\r'; break;
+                case 'n':  *out++ = '\n'; break;
+                case 't':  *out++ = '\t'; break;
+                case 'f':  *out++ = '\f'; break;
+                case 'v':  *out++ = '\v'; break;
+                default:
+                    *out++ = '\\';
+                    *out++ = *str;
+                    break;
+            }
+            ++str;
+            continue;
+        }
+
+        *out++ = *str++;
+    }
+    *out = 0;
+}
+
+static char *ftepp_include_find(ftepp_t *ftepp, const char *file)
+{
+    char *filename = NULL;
+    size_t len;
+
+    if (ftepp->itemname) {
+        const char *last_slash;
+        last_slash = strrchr(ftepp->itemname, '/');
+        if (last_slash) {
+            len = last_slash - ftepp->itemname;
+            memcpy(vec_add(filename, len), ftepp->itemname, len);
+            vec_push(filename, '/');
+        }
+        else {
+            len = strlen(ftepp->itemname);
+            memcpy(vec_add(filename, len), ftepp->itemname, len);
+            if (vec_last(filename) != '/')
+                vec_push(filename, '/');
+        }
+    }
+    len = strlen(file);
+    memcpy(vec_add(filename, len), file, len);
+    vec_push(filename, 0);
+    return filename;
+}
+
+/**
+ * Include a file.
+ * FIXME: do we need/want a -I option?
+ * FIXME: what about when dealing with files in subdirectories coming from a progs.src?
+ */
+static bool ftepp_include(ftepp_t *ftepp)
 {
-	ppmacro *macro;
-	(void)ftepp_next(ftepp);
-	if (!ftepp_skipspace(ftepp))
-		return false;
-
-	switch (ftepp->token) {
-		case TOKEN_IDENT:
-		case TOKEN_KEYWORD:
-			macro = ppmacro_new(ftepp_ctx(ftepp), ftepp_tokval(ftepp));
-			break;
-		default:
-			ftepp_error(ftepp, "expected macro name");
-			return false;
-	}
-
-	(void)ftepp_next(ftepp);
-	if (!ftepp_skipspace(ftepp))
-		return false;
-	if (ftepp->token != TOKEN_EOL) {
-		ftepp_error(ftepp, "stray tokens after macro");
-		return false;
-	}
-	vec_push(ftepp->macros, macro);
-	return true;
+    lex_file *old_lexer = ftepp->lex;
+    lex_file *inlex;
+    lex_ctx  ctx;
+    char     lineno[128];
+    char     *filename;
+
+    (void)ftepp_next(ftepp);
+    if (!ftepp_skipspace(ftepp))
+        return false;
+
+    if (ftepp->token != TOKEN_STRINGCONST) {
+        ftepp_error(ftepp, "expected filename to include");
+        return false;
+    }
+
+    ctx = ftepp_ctx(ftepp);
+
+    unescape(ftepp_tokval(ftepp), ftepp_tokval(ftepp));
+
+    ftepp_out(ftepp, "\n#pragma file(", false);
+    ftepp_out(ftepp, ftepp_tokval(ftepp), false);
+    ftepp_out(ftepp, ")\n#pragma line(1)\n", false);
+
+    filename = ftepp_include_find(ftepp, ftepp_tokval(ftepp));
+    inlex = lex_open(filename);
+    if (!inlex) {
+        ftepp_error(ftepp, "failed to open include file `%s`", filename);
+        vec_free(filename);
+        return false;
+    }
+    vec_free(filename);
+    ftepp->lex = inlex;
+    if (!ftepp_preprocess(ftepp)) {
+        lex_close(ftepp->lex);
+        ftepp->lex = old_lexer;
+        return false;
+    }
+    lex_close(ftepp->lex);
+    ftepp->lex = old_lexer;
+
+    ftepp_out(ftepp, "\n#pragma file(", false);
+    ftepp_out(ftepp, ctx.file, false);
+    snprintf(lineno, sizeof(lineno), ")\n#pragma line(%lu)\n", (unsigned long)(ctx.line+1));
+    ftepp_out(ftepp, lineno, false);
+
+    /* skip the line */
+    (void)ftepp_next(ftepp);
+    if (!ftepp_skipspace(ftepp))
+        return false;
+    if (ftepp->token != TOKEN_EOL) {
+        ftepp_error(ftepp, "stray tokens after #include");
+        return false;
+    }
+    (void)ftepp_next(ftepp);
+
+    return true;
 }
 
 /* Basic structure handlers */
 static bool ftepp_else_allowed(ftepp_t *ftepp)
 {
-	if (!vec_size(ftepp->conditions)) {
-		ftepp_error(ftepp, "#else without #if");
-		return false;
-	}
-	if (vec_last(ftepp->conditions).had_else) {
-		ftepp_error(ftepp, "multiple #else for a single #if");
-		return false;
-	}
-	return true;
+    if (!vec_size(ftepp->conditions)) {
+        ftepp_error(ftepp, "#else without #if");
+        return false;
+    }
+    if (vec_last(ftepp->conditions).had_else) {
+        ftepp_error(ftepp, "multiple #else for a single #if");
+        return false;
+    }
+    return true;
 }
 
 static bool ftepp_hash(ftepp_t *ftepp)
 {
-	ppcondition cond;
-	ppcondition *pc;
-
-	lex_ctx ctx = ftepp_ctx(ftepp);
-
-	if (!ftepp_skipspace(ftepp))
-		return false;
-
-	switch (ftepp->token) {
-		case TOKEN_KEYWORD:
-		case TOKEN_IDENT:
-			if (!strcmp(ftepp_tokval(ftepp), "define")) {
-				return ftepp_define(ftepp);
-			}
-			else if (!strcmp(ftepp_tokval(ftepp), "ifdef")) {
-				if (!ftepp_ifdef(ftepp, &cond))
-					return false;
-				vec_push(ftepp->conditions, cond);
-				return true;
-			}
-			else if (!strcmp(ftepp_tokval(ftepp), "ifndef")) {
-				if (!ftepp_ifdef(ftepp, &cond))
-					return false;
-				cond.on = !cond.on;
-				vec_push(ftepp->conditions, cond);
-				return true;
-			}
-			else if (!strcmp(ftepp_tokval(ftepp), "elifdef")) {
-				if (!ftepp_else_allowed(ftepp))
-					return false;
-				if (!ftepp_ifdef(ftepp, &cond))
-					return false;
-				pc = &vec_last(ftepp->conditions);
-				pc->on     = !pc->was_on && cond.on;
-				pc->was_on = pc->was_on || pc->on;
-				return true;
-			}
-			else if (!strcmp(ftepp_tokval(ftepp), "elifndef")) {
-				if (!ftepp_else_allowed(ftepp))
-					return false;
-				if (!ftepp_ifdef(ftepp, &cond))
-					return false;
-				cond.on = !cond.on;
-				pc = &vec_last(ftepp->conditions);
-				pc->on     = !pc->was_on && cond.on;
-				pc->was_on = pc->was_on || pc->on;
-				return true;
-			}
-			else if (!strcmp(ftepp_tokval(ftepp), "elif")) {
-				if (!ftepp_else_allowed(ftepp))
-					return false;
-				if (!ftepp_if(ftepp, &cond))
-					return false;
-				pc = &vec_last(ftepp->conditions);
-				pc->on     = !pc->was_on && cond.on;
-				pc->was_on = pc->was_on  || pc->on;
-				return true;
-			}
-			else if (!strcmp(ftepp_tokval(ftepp), "if")) {
-				if (!ftepp_if(ftepp, &cond))
-					return false;
-				vec_push(ftepp->conditions, cond);
-				return true;
-			}
-			else if (!strcmp(ftepp_tokval(ftepp), "else")) {
-				if (!ftepp_else_allowed(ftepp))
-					return false;
-				pc = &vec_last(ftepp->conditions);
-				pc->on = !pc->was_on;
-				pc->had_else = true;
-				return true;
-			}
-			else if (!strcmp(ftepp_tokval(ftepp), "endif")) {
-				if (!vec_size(ftepp->conditions)) {
-					ftepp_error(ftepp, "#endif without #if");
-					return false;
-				}
-				vec_pop(ftepp->conditions);
-				break;
-			}
-			else {
-				ftepp_error(ftepp, "unrecognized preprocessor directive: `%s`", ftepp_tokval(ftepp));
-				return false;
-			}
-			break;
-		default:
-			ftepp_error(ftepp, "unexpected preprocessor token: `%s`", ftepp_tokval(ftepp));
-			return false;
-		case TOKEN_EOL:
-			ftepp_errorat(ftepp, ctx, "empty preprocessor directive");
-			return false;
-		case TOKEN_EOF:
-			ftepp_error(ftepp, "missing newline at end of file", ftepp_tokval(ftepp));
-			return false;
-	}
-	return true;
+    ppcondition cond;
+    ppcondition *pc;
+
+    lex_ctx ctx = ftepp_ctx(ftepp);
+
+    if (!ftepp_skipspace(ftepp))
+        return false;
+
+    switch (ftepp->token) {
+        case TOKEN_KEYWORD:
+        case TOKEN_IDENT:
+        case TOKEN_TYPENAME:
+            if (!strcmp(ftepp_tokval(ftepp), "define")) {
+                return ftepp_define(ftepp);
+            }
+            else if (!strcmp(ftepp_tokval(ftepp), "undef")) {
+                return ftepp_undef(ftepp);
+            }
+            else if (!strcmp(ftepp_tokval(ftepp), "ifdef")) {
+                if (!ftepp_ifdef(ftepp, &cond))
+                    return false;
+                cond.was_on = cond.on;
+                vec_push(ftepp->conditions, cond);
+                ftepp->output_on = ftepp->output_on && cond.on;
+                break;
+            }
+            else if (!strcmp(ftepp_tokval(ftepp), "ifndef")) {
+                if (!ftepp_ifdef(ftepp, &cond))
+                    return false;
+                cond.on = !cond.on;
+                cond.was_on = cond.on;
+                vec_push(ftepp->conditions, cond);
+                ftepp->output_on = ftepp->output_on && cond.on;
+                break;
+            }
+            else if (!strcmp(ftepp_tokval(ftepp), "elifdef")) {
+                if (!ftepp_else_allowed(ftepp))
+                    return false;
+                if (!ftepp_ifdef(ftepp, &cond))
+                    return false;
+                pc = &vec_last(ftepp->conditions);
+                pc->on     = !pc->was_on && cond.on;
+                pc->was_on = pc->was_on || pc->on;
+                ftepp_update_output_condition(ftepp);
+                break;
+            }
+            else if (!strcmp(ftepp_tokval(ftepp), "elifndef")) {
+                if (!ftepp_else_allowed(ftepp))
+                    return false;
+                if (!ftepp_ifdef(ftepp, &cond))
+                    return false;
+                cond.on = !cond.on;
+                pc = &vec_last(ftepp->conditions);
+                pc->on     = !pc->was_on && cond.on;
+                pc->was_on = pc->was_on || pc->on;
+                ftepp_update_output_condition(ftepp);
+                break;
+            }
+            else if (!strcmp(ftepp_tokval(ftepp), "elif")) {
+                if (!ftepp_else_allowed(ftepp))
+                    return false;
+                if (!ftepp_if(ftepp, &cond))
+                    return false;
+                pc = &vec_last(ftepp->conditions);
+                pc->on     = !pc->was_on && cond.on;
+                pc->was_on = pc->was_on  || pc->on;
+                ftepp_update_output_condition(ftepp);
+                break;
+            }
+            else if (!strcmp(ftepp_tokval(ftepp), "if")) {
+                if (!ftepp_if(ftepp, &cond))
+                    return false;
+                cond.was_on = cond.on;
+                vec_push(ftepp->conditions, cond);
+                ftepp->output_on = ftepp->output_on && cond.on;
+                break;
+            }
+            else if (!strcmp(ftepp_tokval(ftepp), "else")) {
+                if (!ftepp_else_allowed(ftepp))
+                    return false;
+                pc = &vec_last(ftepp->conditions);
+                pc->on = !pc->was_on;
+                pc->had_else = true;
+                ftepp_next(ftepp);
+                ftepp_update_output_condition(ftepp);
+                break;
+            }
+            else if (!strcmp(ftepp_tokval(ftepp), "endif")) {
+                if (!vec_size(ftepp->conditions)) {
+                    ftepp_error(ftepp, "#endif without #if");
+                    return false;
+                }
+                vec_pop(ftepp->conditions);
+                ftepp_next(ftepp);
+                ftepp_update_output_condition(ftepp);
+                break;
+            }
+            else if (!strcmp(ftepp_tokval(ftepp), "include")) {
+                return ftepp_include(ftepp);
+            }
+            else if (!strcmp(ftepp_tokval(ftepp), "pragma")) {
+                ftepp_out(ftepp, "#", false);
+                break;
+            }
+            else {
+                ftepp_error(ftepp, "unrecognized preprocessor directive: `%s`", ftepp_tokval(ftepp));
+                return false;
+            }
+            break;
+        default:
+            ftepp_error(ftepp, "unexpected preprocessor token: `%s`", ftepp_tokval(ftepp));
+            return false;
+        case TOKEN_EOL:
+            ftepp_errorat(ftepp, ctx, "empty preprocessor directive");
+            return false;
+        case TOKEN_EOF:
+            ftepp_error(ftepp, "missing newline at end of file", ftepp_tokval(ftepp));
+            return false;
+
+        /* Builtins! Don't forget the builtins! */
+        case TOKEN_INTCONST:
+        case TOKEN_FLOATCONST:
+            ftepp_out(ftepp, "#", false);
+            return true;
+    }
+    if (!ftepp_skipspace(ftepp))
+        return false;
+    return true;
 }
 
 static bool ftepp_preprocess(ftepp_t *ftepp)
 {
-	bool newline = true;
-
-	ftepp->lex->flags.preprocessing = true;
-
-	ftepp_next(ftepp);
-	do
-	{
-		if (ftepp->token >= TOKEN_EOF)
-			break;
-
-		ftepp->newline = newline;
-		newline = false;
-
-		switch (ftepp->token) {
-			case '#':
-				if (!ftepp->newline) {
-					printf("%s", ftepp_tokval(ftepp));
-					ftepp_next(ftepp);
-					break;
-				}
-				if (ftepp_next(ftepp) >= TOKEN_EOF) {
-					ftepp_error(ftepp, "error in preprocessor directive");
-					ftepp->token = TOKEN_ERROR;
-					break;
-				}
-				if (!ftepp_hash(ftepp))
-					ftepp->token = TOKEN_ERROR;
-				break;
-			case TOKEN_EOL:
-				newline = true;
-				printf("\n");
-				ftepp_next(ftepp);
-				break;
-			default:
-				printf("%s", ftepp_tokval(ftepp));
-				ftepp_next(ftepp);
-				break;
-		}
-	} while (!ftepp->errors && ftepp->token < TOKEN_EOF);
-
-	ftepp_delete(ftepp);
-	return (ftepp->token == TOKEN_EOF);
+    ppmacro *macro;
+    bool     newline = true;
+
+    ftepp->lex->flags.preprocessing = true;
+    ftepp->lex->flags.mergelines    = false;
+    ftepp->lex->flags.noops         = true;
+
+    ftepp_next(ftepp);
+    do
+    {
+        if (ftepp->token >= TOKEN_EOF)
+            break;
+#if 0
+        ftepp->newline = newline;
+        newline = false;
+#else
+        /* For the sake of FTE compatibility... FU, really */
+        ftepp->newline = newline = true;
+#endif
+
+        switch (ftepp->token) {
+            case TOKEN_KEYWORD:
+            case TOKEN_IDENT:
+            case TOKEN_TYPENAME:
+                macro = ftepp_macro_find(ftepp, ftepp_tokval(ftepp));
+                if (!macro) {
+                    ftepp_out(ftepp, ftepp_tokval(ftepp), false);
+                    ftepp_next(ftepp);
+                    break;
+                }
+                if (!ftepp_macro_call(ftepp, macro))
+                    ftepp->token = TOKEN_ERROR;
+                break;
+            case '#':
+                if (!ftepp->newline) {
+                    ftepp_out(ftepp, ftepp_tokval(ftepp), false);
+                    ftepp_next(ftepp);
+                    break;
+                }
+                ftepp->lex->flags.mergelines = true;
+                if (ftepp_next(ftepp) >= TOKEN_EOF) {
+                    ftepp_error(ftepp, "error in preprocessor directive");
+                    ftepp->token = TOKEN_ERROR;
+                    break;
+                }
+                if (!ftepp_hash(ftepp))
+                    ftepp->token = TOKEN_ERROR;
+                ftepp->lex->flags.mergelines = false;
+                break;
+            case TOKEN_EOL:
+                newline = true;
+                ftepp_out(ftepp, "\n", true);
+                ftepp_next(ftepp);
+                break;
+            default:
+                ftepp_out(ftepp, ftepp_tokval(ftepp), false);
+                ftepp_next(ftepp);
+                break;
+        }
+    } while (!ftepp->errors && ftepp->token < TOKEN_EOF);
+
+    newline = ftepp->token == TOKEN_EOF;
+    return newline;
+}
+
+/* Like in parser.c - files keep the previous state so we have one global
+ * preprocessor. Except here we will want to warn about dangling #ifs.
+ */
+static ftepp_t *ftepp;
+
+static bool ftepp_preprocess_done()
+{
+    bool retval = true;
+    lex_close(ftepp->lex);
+    ftepp->lex = NULL;
+    if (vec_size(ftepp->conditions)) {
+        if (ftepp_warn(ftepp, WARN_MULTIFILE_IF, "#if spanning multiple files, is this intended?"))
+            retval = false;
+    }
+    if (ftepp->itemname) {
+        mem_d(ftepp->itemname);
+        ftepp->itemname = NULL;
+    }
+    return retval;
 }
 
 bool ftepp_preprocess_file(const char *filename)
 {
-	ftepp_t *ftepp = ftepp_init();
     ftepp->lex = lex_open(filename);
+    ftepp->itemname = util_strdup(filename);
     if (!ftepp->lex) {
         con_out("failed to open file \"%s\"\n", filename);
         return false;
     }
-    return ftepp_preprocess(ftepp);
+    if (!ftepp_preprocess(ftepp)) {
+        ftepp_delete(ftepp);
+        return false;
+    }
+    return ftepp_preprocess_done();
 }
 
 bool ftepp_preprocess_string(const char *name, const char *str)
 {
-	ftepp_t *ftepp = ftepp_init();
     ftepp->lex = lex_open_string(str, strlen(str), name);
+    ftepp->itemname = util_strdup(name);
     if (!ftepp->lex) {
         con_out("failed to create lexer for string \"%s\"\n", name);
         return false;
     }
-    return ftepp_preprocess(ftepp);
+    if (!ftepp_preprocess(ftepp)) {
+        ftepp_delete(ftepp);
+        return false;
+    }
+    return ftepp_preprocess_done();
+}
+
+bool ftepp_init()
+{
+    ftepp = ftepp_new();
+    return !!ftepp;
+}
+
+const char *ftepp_get()
+{
+    return ftepp->output_string;
+}
+
+void ftepp_flush()
+{
+    vec_free(ftepp->output_string);
+}
+
+void ftepp_finish()
+{
+    if (!ftepp)
+        return;
+    ftepp_delete(ftepp);
+    ftepp = NULL;
 }